(1) Field of the Invention
The present invention relates generally to grinding tools and more particularly to grinding tools for use in edge grinding of sheet glass. Use of the grinding wheel of this invention may improve glass quality and reduce process downtime.
(2) Background Information
The use of diamond containing abrasive wheels to contour and/or chamfer the edge of flat glass (also referred to herein as sheet glass), such as that used in the automotive, architectural, furniture, and appliance industries, is well known and is typically carried out for both safety and cosmetic reasons. The abrasive wheels of the prior art include a profiled, bonded abrasive matrix disposed in a recess at the periphery of the wheel (see U.S. Pat. No. 3,830,020 to Gomi and U.S. Pat. No. 4,457,113 to Miller). During an edge grinding operation, periodic reprofiling of the abrasive is typically required to produce consistent high quality glass. For optimum economic results it is typically desirable to minimize the downtime associated with reprofiling and to bring newly reprofiled wheels back on-line with minimal break-in and/or conditioning.
Therefore, there exists a need for a grinding tool and/or method for edge grinding of sheet glass that may provide for reduced downtime and/or improved grinding performance.
One aspect of the present invention includes a grinding tool for shaping an edge of a glass sheet. The grinding tool includes an arbor and a wheel, the arbor and wheel being of unitary construction and having a common axis of rotation. The grinding tool further includes a recess extending along a periphery of the wheel with a bonded abrasive disposed therein. The bonded abrasive is sized and shaped for being profiled, to shape an edge of a glass sheet upon rotation of the tool about the axis. In one variation of this aspect the bonded abrasive may be further sized and shaped for being re-profiled after use.
In another aspect, this invention includes a method for shaping an edge of a glass sheet. The method includes providing a grinding tool as described in the proceeding paragraph, rotating the grinding tool about the axis, and applying the bonded abrasive to the edge of the glass sheet. In one variation of this aspect, the method further includes reprofiling the bonded abrasive.
In still another aspect, this invention includes a method for profiling an abrasive matrix in a grinding tool. The method includes providing a grinding tool as described in the proceeding paragraph and machining a profile in an outer surface of the bonded abrasive matrix. In one variation of this aspect, the machining includes an electro discharge machining operation.